Features and Benefits: Services transfer cases, engine oil pans, manual transmission and differential drain and fill plugs; For use with 3/8 in. square drives tools; Services: Transfer cases, Engine oil pans, Manual transmission, Differential drain plugs & Fill plugs; Forged from the finest chrome-molybdenum alloy steel, the best choice for strength; Square Male Socket, 10mm, 4 Point, 3/8″ Drive